class value_compare
: public binary_function<value_type, value_type, bool> {
public:
bool operator()(const value_type& x, const value_type& y)
{return (comp(x.first, x.second)); }
protected:
value_compare(key_compare pr)
: comp(pr) {}
key_compare comp;
};
The type describes a function object that can compare the sort keys in two elements to determine their relative order in
the controlled sequence. The function object stores an object comp
of type key_type
. The member function
operator()
uses this object to compare the sort-key components of two elements.